I don't know of any other idTech 5 games in development and I wouldn't hold your breath for any either. I can't see many dev's comparing the feasibility of Cryengine or UE4 against idTech 5 and choosing idTech 5. I'm curious to see what id does with idTech 6 for Doom though. It'll be interesting to see how much of a departure from 5 it is.